The present invention generally relates to motor vehicle equipment and more particularly, to an improved slider for use in an automatic seat belt arrangement to be used in a motor vehicle for protection of a driver or passenger, and arranged to be automatically fastened or applied after the driver or passenger has taken his or her seat.
In the first place, one example of the automatic seat belt arrangement of this kind will be explained hereinbelow for better understanding.
Referring to FIGS. 1 and 2, the automatic seat belt arrangement is adapted to maintain a driver or passenger (not shown) in a restricted state by an outer webbing Wo and an inner webbing Wi. More specifically, one end of the outer webbing Wo extending across a seat S is connected to a rear lower portion of a vehicle door D through a buckle unit B which makes it possible to disengage the outer webbing Wo when necessary. Meanwhile, the other end of the outer webbing Wo is connected to a guide rail 10 mounted on a roof side R which constitutes one of side walls of the vehicle. As shown in FIG. 3, the guide rail 10 having a generally U-shaped cross section is formed therein with an anchor groove 11 for receiving therein an enlarged slider head portion 4 of a slider 1 to be described more in detail later, and lower slide groove 12 in which a driving tape 13 is slidably accommodated, while the end of the outer webbing Wo is coupled to a leg portion 2 of the slider 1. For such coupling, the end of the outer webbing Wo is fixed, by sewing, to an anchor plate 15 pivotally connected to the leg portion 2 of the slider 1 by a pin P engaged with a nut N, or detachably connected through a buckle device and the like (not shown).
The driving tape 13 accommodated in the lower slide groove 12 of the guide rail 10 is arranged to be movable in the longitudinal direction of the guide rail 10, and as the driving tape 13 is displaced, the slider 1 is also moved in the longitudinal direction of said guide rail 10. The driving tape 13 is capable of transmitting a pulling force and a pushing force in the longitudinal direction, and is arranged to be automatically driven through a sprocket arrangement (not shown), so that upon opening of the door D for entrance or exit of the passenger as shown in FIG. 2, the slider 1 is displaced towards the forward end of the guide rail 10 so as to bring the outer webbing Wo into a released state spaced from the seat S so as to permit free entrance or exit of the passenger, while upon closing of the door D, said slider 1 is moved to the rear end portion of the guide rail 10 and brings the outer webbing Wo close to the seat S, into a state ready to be fastened or applied to the passenger as shown in FIG. 1.
An intermediate portion of the outer webbing Wo respectively connected, at its opposite ends, to the door D and the roof side R as described above, extends through a through-ring O, which is also connected to the forward end of the inner webbing Wi, with a base portion of the inner webbing Wi being arranged to be wound onto a winding unit M. The winding unit M, adapted to wind up the inner webbing Wi by a biasing force, incorporates therein an inertia locking mechanism (not shown) for instantaneously suspending paying out of the webbing Wi by an acceleration sensor such as a pendulum or the like (not shown) in case of emergency for the motor vehicle. It is to be noted that the inner webbing Wi is arranged to be paid out from the winding unit M without being locked, when the door D is opened as shown in FIG. 2.
As is seen from the above description, the automatic seat belt arrangement has the construction as explained so far, and upon closing of the door D after the driver or passenger is seated on the seat S, the webbings Wo and Wi are automatically brought into the state ready to be fastened for enabling the passenger to wear the three point type seat belt. It is to be noted that the structure of the webbings Wo and Wi may be modified, depending on necessity, for example, into a shoulder belt and a lap belt (not shown) separately provided. Thus, the automatic seat belt arrangement as described in the foregoing is provided to eliminate the inconvenience for attaching or detaching the seat belt at each time of entrance or exit, and also to prevent the driver from driving the motor vehicle without fastening the seat belt due to troublesome procedures as described above.
Incidentally, as shown in FIG. 10, for manufacturing a slider F similar to the slider 1 as described earlier, it has been a conventional practice to prepare a slider main body Fb by hot-forging or casting, and to form an enlarged slider head portion (not shown) and a driving tape mounting portion (not shown) by molding of a synthetic resin, respectively at a head portion Fh and an intermediate mounting portion Fi of the main body Fb.
However, in the known practice as described above, there has been such a disadvantage that owing to the structure of the slider F, it is difficult to process the slider main body Fb in an efficient manner, with a consequent high manufacturing cost involved.